This invention relates generally to roll baling machines typically referred to as "round balers" which form cylindrical bales of crop material and, in particular, to a twine wrapper trip mechanism for such machines.
U.S. Pat. No. 4,771,595 to R. E. Jennings discloses a round baler having a plurality of rollers that cooperate with an apron consisting of a plurality of belts to form cylindrical bales. Take up arms for the apron are rotatably mounted in a tailgate of the baler. Consequently, the take up arms are lifted whenever the tailgate is raised. Mounting the take up arms in the tailgate causes a problem when a conventional type of automatic twine wrapper such as disclosed in U.S. Pat. No. 4,167,844 to J. H. Freimuth et al is installed on the baler of the Jennings patent. This type of twine wrapper is automatically tripped into operation by the apron take up arms as they rotate during bale formation. However, with the type of twine wrapper disclosed in the Freimuth et al patent installed on the baler disclosed in the Jennings patent, the apron take up arms will improperly trip the twine wrapper into operation whenever the tailgate is raised. Such improper tripping of the twine wrapper is undesirable.